How to Propagate a Butterfly Bush
- 1). Cut several stem cuttings—6 to 8 inches in length—from a healthy butterfly bush. Make the initial cut just below a leaf node. The top of the stem cutting should be slightly above a leaf node. Place the cuttings in water to retain as much moisture as possible before planting.
- 2). Moisten potting soil only to the point of feeling like a damp sponge. Fill a growing tray with the potting soil. Use a dibble to create evenly spaced holes in the soil for the stem cuttings. If you don't have a dibble use your finger or a pencil. Make the holes about 3 inches deep.
- 3). Pour 3 to 4 tsp. of rooting hormone onto a paper plate. Remove all but two or three sets of leaves off the stem cuttings. Dip the bottom 3 inches of the stem cutting into the rooting hormone. Shake off the excess powder and stick the cutting into the preformed holes. Firm the soil around the cuttings so they stand erect.
- 4). Cover the growing tray with clear plastic wrap or place it in a clear bag. Place the growing tray in a bright location but out of direct sunlight. Check the stem cuttings every few days to maintain moisture in the soil and remove dead or dying cuttings. Check for mold growth and remove infected cuttings immediately.
- 5). Continue monitoring the stem cuttings until you can tug on the leaves and feel resistance. This indicates roots are developing. Allow the cuttings to grow for another week and then transplant them into separate containers.
- 6). Harden off the new plants by moving them outside, into a shaded area, during warm weather. Gradually move the plants into direct sunlight. When the plants have been brought gradually to a tolerance of all-day exposure to the sun, plant them wherever you prefer.
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